Issue #4380: The queue drain logic was using typeof === 'number'
to check for thread IDs, which fails for Slack where thread_ts
is a string like '1737766124.329349'.
Changed three occurrences:
- Line 43: typeof threadId !== 'number' → threadId == null
- Line 49: typeof threadId === 'number' → threadId != null
- Line 75: typeof originatingThreadId === 'number' → originatingThreadId != null
This allows Slack string thread IDs to be properly recognized
while still filtering out undefined/null values.
